This invention relates to a ring binder particularly for use in a loose-leaf binder, being especially directed to a ring binder wherein each ring is formed of a flexible strap.
In the background may be noted the following U.S. Patents received by the assignee of this invention:
U.S. Pat. No.DateTitle5,354,142Oct. 11, 1994Ring Binder5,577,852Nov. 26, 1996Ring BinderMechanism5,755,513May 26, 1998Ring Binder5,842,807Dec. 1, 1998Ring Binder5,879,097Mar. 9, 1999Ring Binder6,033,144Mar. 7, 2000Ring BinderMechanism6,168,339Jan. 2, 2001Ring Binder
Also in the background is U.S. Pat. No. 3,315,682, issued Apr. 25, 1967, entitled Loose Leaf Notebook Binder, on account of its showing of a ring formed from a flexible strap. This invention is regarded as involving substantial improvement thereover.
Ring binders generally include metallic ring members which are pivotally connected to a hinge mechanism on a spine for opening and closing opposed ring members. In the open position, the ring members are spaced apart to allow pages of loose-leaf paper or the like which have pre-formed holes to be received on one set of ring members. In the closed position, the opposed ring members are engaged to form a continuous ring on which the pages can be turned. Typically, the ring members and rings which they form have a fixed size and cannot be adjusted in accordance with the amount of paper being held by the ring binder. Consequently, the ring members may be either too small or too large.